| Type | MGI:General | Description | most prominent defects are seen at the spermatid stage of spermiogenesis, where abnormally elongated and constricted sperm heads are seen analysis of sperm head shaping indicates normal acrosome and nucleus morphology from step 1 to step 8 and normal morphology of elongated heads at step 9-10 but abnormal club-shaped heads at step 11 spermatids which become more apparent between step 11 and 16 mice show impaired sperm flagellum biogenesis, with absent axoneme in step 2-3 spermatids and abnormally formed flagella during step 4-6 mice show impaired manchette function |
